Total depth after etching is 9.037 um
Calculated remaining resist as 8.99um, indicating an erosion of -0.25um in 10 minutes of etching
This equates to an erosion rate of -25 nm/min
The etch depth of 0.05um in 10 mins indicates an etch rate of 5.0nm/min
The selectivity is therefore -0.20:1